Help slow algae clean up

[Rene9111959]

This is the first year that we have left the water in the pool all winter. I am having problems getting rid of the algae. We painted pool last year with EVM coating, to seal some cracks in the concrete it is holding water well. We covered pool with tarp, but it slipped and leaves got in. We have been cleaning out leaves since we opened first of June. Used commercial algaecides, a pool opening kit from In the Swim.
Found your website and am trying for TFP. Bought the recommended test kit.
We have been slamming it for a week, keeping FC at 35. PH was at 7.2 when we started. Cyanuric acid was at 90 on Sunday, but yesterday at 75 (lot of backwashing and adding new water). TC has been at 1.5 consistent. Hardness was 110 on Sunday. We have been using bleach to keep level up. Vacuuming, backwashing, and brushing at least once a day, if not more.
Opened the sand filter and stirred up the sand some. Added some DE powder to the water, not the filter.
It is very, very slowly getting better.
Any ideas?

 

[Abigail K]

How often are you testing the water and adding bleach?

 

[Rene9111959]

2-3 times a day. We did it more often at first, but it seems to be stable for 3-4 hrs at a time.
test this am
CYA 80 (a nephew add some chlorine tablets to help keep up chlorine level, which brought ca back up, they are coming out this morning.)
FC 27 (I forgot to adjust shock level to CYA yesterday, so today we will up FC to 31 via pool math)

Last test yesterday was at 2:30pm. We brought FC up to 35 at that point.

Should I be testing TA at this point?

Using Taylor k-2006 testing.


We are going to add DE to the sand filter today, per instructions on here.

 

[Abigail K]

Ignore TA for the mean time. Playing with TA is something you leave for when you're bored.

Please do NOT use any more tablets, your CYA (we use the acronym "CYA" and not "CA" for cyanuric acid to prevent confusion) is high enough as it is.
Your nephew may have the best intentions, but continued use of tablets will trigger a need to do a partial drain & refill. We want you to avoid that because that means draining away some of your hard work.
To SLAM properly, you must use bleach only otherwise it throws everything out of whack.

SLAM level for CYA 80 is 31, correct.

FC holding for 3-4 hours at a time is an indication of progress - it means that the algae is being killed off. Please continue to SLAM.

Last test yesterday was at 2:30pm. We brought CA up to 35 at that point.

I'm not sure I understood what you meant correctly. Do you mean you brought up your CYA levels to 35? If so, where were they before that? You mentioned that CYA was 75 on 17th June.

 

[Rene9111959]

Thanks.
Tablets have been removed.
They may get out the regulator and air compressor and vacuum manually to see what is left on the bottom.
I have been using advice for vinyl pool, because of the coating. Is that OK. Nothing on here about concrete.

 

[Abigail K]

In the short term, no.
SLAM values and SLAMming are not affected by the surface.
The surface becomes more important for long-term maintenance.
Someone else would be able to give a more definitive answer before this becomes an issue - focus on SLAMming for now.

Can you please answer my previous question about bringing the CA to 35?

 

[Rene9111959]

Was supposed to be FC, not CA, I corrected it. Sorry.
We brought the free chlorine level back up to 35.

 

[Beens]

Sounds like you just need to keep SLAMming! Make sure you're bringing that FC up to SLAM level as often as you can and keep brushing.

Since your CYA is so high you *could* vacuum to waste if your filter has that setting. I see you mentioned a compressor so I guess you have another way of doing that? You'll be able to lower your CYA a bit when you refill and you'll also hopefully get some hidden gunk that may be lurking on the bottom.

If you've got anything hanging around down there it can definitely slow down the SLAM process so anything you do to get it out, vacuum/brush/leaf rake, will help!

 

[Casey]

If you're not running a SWG, I would actually go ahead and do a partial drain/refill. You could use the chlorine more wisely with a lower CYA level.

 

[Rene9111959]

Compressor is for the regulator so the teenage boys can scuba dive to bottom and stay under and vacuum with just the hose and see what they are vacuuming to get more out.
I was just reading about vacuuming to waste and that is a great idea.
Scuba diving to clean was one of my father's ideas to keep the guys interested!

FC was 31 this afternoon, brought it back up to 31.

I am going out now to retest and add DE to filter.